A microreactor has attracted attention as a reactor which substitutes for a conventional batch reactor, and various studies are being made on the microreactor. The “microreactor” is a general term for flow-type reaction apparatuses, of which the space scale of a reaction system is, for example, some micrometers, wherein a chemical or biochemical reaction is conducted in the reaction system. The microreactor has a transport path for a substance used in a reaction. The transport path has an inner diameter of, for example, some micrometers. In the microreactor, a plurality of substances can be efficiently mixed to cause a reaction. Further, the reaction can proceed uniformly at a constant temperature. Therefore, by using the microreactor, not only can the reaction selectivity be improved, but also the reaction rate can be increased. Further, it is said that the microreactor can be more easily scaled up than a conventional batch reactor from the laboratory scale to the production process scale. However, the microreactor has a high production cost as well as a lot of technical problems. For this reason, not many microchemical plants aimed for production have been realized.
The microreactor has lower productivity than that of a conventional batch reactor. For increasing the production of a microchemical plant, a method called numbering-up is studied. The numbering-up is a method of arranging a plurality of microreactors in parallel.
The numbering-up can be realized by arranging the same many apparatuses having a pump in parallel. The numbering-up method has a problem in that the production cost for the apparatus is high. This method is advantageous in that the process can be scaled up from the laboratory scale to the production scale without changing, e.g., the reaction conditions, and hence is easily industrialized.
Patent document 1 has a description of a numbering-up method in which a channel is branched. This method is a method in which a liquid raw material fed from a pump is distributed to a plurality of branched channels and mixers are arranged in parallel.
Patent document 2 has a description of a method in which a liquid is uniformly distributed to a plurality of microreactors without using a branched pipe.
Patent document 3 has a description of a microchannel reactor comprising a plurality of stacked channel units.
Patent document 4 has a description of a microreactor which is aimed at reducing the microchemical plant in cost and size.